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Weather satellites detect 515-mile-long lightning flash

space.com

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Re: Weather satellites detect 515-mile-long lightning flash

#3
> It's 2017, and a thunderstorm shoots off a lightning bolt. ... . It sets a new world record, besting the previous title holder — a 477-mile (768-km) bolt from 2020

So the previous record holder never should have held it at all (an earlier one beats a later one)? How was that missed? Is there that much data to sift through? Why is that not addressed in the article?

Re: Weather satellites detect 515-mile-long lightning flash

#4

> It's 2017, and a thunderstorm shoots off a lightning bolt. ... . It sets a new world record, besting the previous title holder — a 477-mile (768-km) bolt from 2020 So the previous record holder never should have held it at all (an earlier one beats a later one)? How was that missed? Is there that much data to sift through? Why is that not addressed in the article?

From the linked paper[0], "In 2024, the entire GLM data record was reprocessed with new computational methods whose improved efficiency allowed difficult portions of the data record to be examined. This reprocessing inspired a reevaluation of the 2017 megaflash[...] after it identified a hitherto-overlooked discharge"

[0] https://journals.ametsoc.org/view/journals/bams/aop/BAMS-D-2...

Re: Weather satellites detect 515-mile-long lightning flash

#6
Interesting (to me) that the flash shown on the included diagram has positive and negative branches. That suggests to me that while it is one "flash", it is actually multiple discharges, one triggering others in a chain-reaction-like process. Anyone know how these things work?

Re: Weather satellites detect 515-mile-long lightning flash

#7
post #6

Interesting (to me) that the flash shown on the included diagram has positive and negative branches. That suggests to me that while it is one "flash", it is actually multiple discharges, one triggering others in a chain-reaction-like process. Anyone know how these things work?

The simplest possible lightning bolt would be a straight line with a positive side and a negative side, no? If so, isn't that a single discharge?

Certainly what you're describing happens. You see the effect in the spark gaps of a Marx generator: one discharge triggers the next. I'm just saying that it's not necessarily the case that multiple differently charged branches mean spatially disconnected bolts. The path of least resistance is going to be through a nearby bolt of lightning, supposing one exists (plasma being a good conductor) so I'd expect they have a tendency to merge, so you get a network of sources and sinks. Probably as new nodes join the network what was once a source could become a sink--the channel being open for further equalization with new distant point.

Whether to count that as one thing or many, idk.

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